personally I would be hesitant to use a knock off cleat for this application, if the cleat/pedal interface does not work then release is likely to be impacted, which could end up hurting
as I recall speedplay had all sorts of lubrication requirements both pedal and cleat (was long time ago....did not like speedplay pedals so not lots of experience, but som)
the only safe solution is a new pedal system
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